The present invention relates to a control device for a hybrid vehicle that uses an engine and a drive motor together as a source of power.
A hybrid vehicle, which uses an internal combustion engine such as a gasoline engine and an electric motor together as a source of power of the vehicle, includes a series and parallel type. This type of hybrid vehicle is provided with a power generator in addition to the engine and the drive motor, and driving of the vehicle is shifted to any one of driving by the engine, driving by the drive motor, and driving by both of the engine and the motor depending on a running state, whereby the power generator can be driven by the engine at a time of running by the drive motor. The hybrid vehicle can be changed to a motor drive mode of driving the vehicle only by the drive motor, and an engine drive mode of driving the vehicle by the engine or by the drive motor as well as the engine. For example, the vehicle can be driven by the drive motor at a starting time when driving torque is required, and the vehicle can be driven by the engine when a vehicle speed is increased, and the vehicle can be driven by the drive motor and the engine at a high-load running time such as a uphill running time (see Japanese Patent Laid-open No. 2000-289472). The running in which the vehicle is driven by both of the engine and the drive motor under the engine drive mode is also called as a parallel running type.